Waardenburg syndrome - Hereditary deafness that is characterized by hearing impairment, a white shock of hair, and/or distinctive blue color to one or both eyes, as well as wide-set inner corners of the eyes; balance problems are also associated with some types of Waardenburg syndrome.
wart - a non-cancerous skin growth caused by a virus.
watermelon stomach - parallel red sores in the stomach that look like the stripes on a watermelon.
wedge resection of the lung - a small, localized section of the lung is removed - often for a lung biopsy.
white blood cells (Also called WBCs or leukocytes.) - blood cells involved in the destruction of viruses, bacteria, and fungi.
white matter - nerve tissue that is paler in color than gray matter because it contains nerve fibers with large amounts of insulating material (myelin). The white matter does not contain nerve cells. In the brain, the white matter lies within the gray layer of the cerebral cortex.
whole blood - blood containing all its components, such as red and white blood cells, platelets, and more.
Wolff-Parkinson-White syndrome - An extra electrical pathway that connects the atria and ventricles and causes rapid heartbeat.